Network of new quaternary borate glasses Bi2O3–Y2O3–Al2O3–B2O3 was studied by FTIR and UV spectroscopies. According to the FTIR results, the addition of Y2O3 increases the amount of bridging oxygens and changes the coordination number of the glasses by creating [BO4] structural units. FTIR investigations explained the increase of the computed elastic moduli according to Makishima–Mackenzie model. The optical parameters such as the UV transmission, the polarizability, and the basicity are found to be sensitive to the concentration of Y2O3. The results of the elastic moduli and the optical parameters were interpreted in terms of the vibrations of structural groups and the strength of the bonds.

This study reports on the optical parameters of MoO3–V2O5–PbO films. The measured transmittance spectra in the spectral range 300–2500 nm was used for precise calculations of the complex index of refraction (real (n) and imaginary (k) parts) as well as the film thicknesses. With the addition of MoO3, a blue shift of the absorption edge was represented while the index of refraction (n) was decreased. The decrease of the index of refraction was discussed in terms of the dispersion model. A good correlation between the bulk modulus Kop, the optical band gap Eg and the index of refraction was observed. With the help of Kop, Eg and n values, the electronic polarizability has been calculated for the films under study. The results well discussed in terms of the density, electronegativity and polarizability changes due to the addition of MoO3 content.

In the present work, Al-Mg-Zn alloys with compositions of Al- 2 at.% Zn — x at.% Mg, (x=1.8, 2, 2.4, 3 and 4.2) have been investigated. The developed precipitates and their growth have been followed as a function of aging temperature. The precipitates morphology was examined by scanning electron microscope (SEM) and correlated with the microhardness (HV) and differential scanning calorimetry (DSC) of the specimens. The structure of the precipitates has been detected by X-ray diffraction (XRD). Mostly, the precipitates are characterized as T′, T, η′ and η phases. The XRD charts analysis show that T′(Mg32 (Al, Zn)49) and T (Mg32 (Al, Zn)49) are cubic whereas η′ (MgZn2) and η (MgZn2) are hexagonal.η′ andrη phases have had a hexagonal structure of the same composition with slight different lattice parameters .

The effect of temperature in the range of 300–450 K and the indium content on the electrical and thermoelectric properties of Ge20Se80−xInx (0.0≤x≤24 at%) chalcogenide glassy thin films have been studied. From dc electrical and thermoelectric measurements, it was observed that the activation energies for electrical conductivity (ΔE) and for thermoelectric (ΔEs) decrease while the conductivity (σ) and Seebeck coefficient (S) increase upon introducing In into the Ge–Se glasses. In contrast to the behavior obtained with Bi or Pb doping, In incorporated in Ge–Se does not lead to a p-to n-type conduction inversion. The power factor (P) which is strongly depends on both of the Seebeck coefficient and the electrical conductivity. According to the obtained results, the Ge20Se80−xInx films can be considered potential candidates for incurring high action thermoelectric materials.

Different compositions of amorphous Ge15Se85-xCux thin films were deposited onto glass substrates by the thermal evaporation technique. Their amorphous structural characteristics were studied by X-ray diffraction (XRD). The optical constants (n, k) of amorphous Ge15Se85-xCux thin films were obtained by fitting the ellipsometric parameters (j and D) data for the first time using three layers model system in the wavelength range 300e1100 nm. It was found that the refractive index, n, increases with the increase of Cu content. The possible optical transition in these films is found to be indirect transitions. The optical energy gap decreases linearly from 1.83 to 1.44 eV with increasing the Cu. The experimental transmittances spectrum can be simulated using the thickness and optical constants modeled by spectroscopic ellipsometry model.

The variations in structure and optical properties of amorphous a-Se and a-M5Se95 (M = Ge, Ga and Zn) films have been studied based on FTIR and optical measurements. FTIR transmittance spectra for a-Se and a-M5Se95 (M = Ge, Ga and Zn) glasses were measured as a function of wavenumber. The addition of Ge, Ga and Zn increases the vibrational frequency of the a-Se main band. The absorption edge of Ge5Se95 shifted towards long side of the wavelength in comparison with that of a-Se film. This shift increases gradually in the case of Ga5Se95 and Zn5Se95 films. So, the optical bandgap ofM5Se95 films was decreased, but the index of refraction was increased. The first and third order of electric susceptibility (χ(1) and χ(3)) and non-linear index of refraction (n2) were increased by adding Ge, Ga and Zn into a-Se.

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Porous anodic alumina (PAA) templates have been extensively studied due to their unique morphology and extensive applications.The fabrication of PAAcan bemodulated to achieve a self-ordered pore structure with desired pore size and interpore separation.PAAthin film templateswere fabricated fromsilicon doped aluminumfilm,Al-1wt%Si, based on one-step anodization method at 22 °C. Effects of anodizing potential (10–20V) as well as sulfuric acid concentrations (0.6–1.8M) on current density, interpore distance, anodization rate, and volume expansion were evaluated.The results indicated that current density increased largely exponentially with a concentration of the electrolyte at a given anodizing voltage. In addition, distinct andwell-ordered pores were obtained for anodization conducted at 15Vand 20 V. The volume expansion factor is proportional to the applied voltage. At 1.8Msulfuric acid, the expansion factor increases with pore regularity with 1.4 considered as the transition point.Theminimumcurrent density (2.1±0.15mAcm−2) was observed at theminimumanodizing condition (0.6M, 10V).Also,maximumanodizing condition (1.8M, 20V) resulted in the highest current density of 34±4mAcm−2.As expected, anodization time decreaseswith an increase in both anodization voltage and electrolyte concentration.

Ge-In-Se system, similar to many other chalcogenide glasses, has attracted much attention due to its interesting physical properties and applications. This article reports thermal analysis and estimation of activation energies of the glass transition and amorphous-crystallization transformation of Ge13In8Se79 chalcogenide glass. The kinetic parameters were investigated under a non-isothermal condition at different heating rates (7–40 K/min) using differential scanning calorimetric (DSC) technique. The amorphous nature of the samples was confirmed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The activation energy was calculated from DSC data using five isoconversional methods: Kissinger–Akahira– Sunose (KAS), Flynn–Wall–Ozawa (FWO), Tang, Starink, and Vyazovkin. The results confirm that the activation energy of crystallization varies and depends on the degree of crystallization as well as temperature. It was also observed that the transformation from amorphous to the crystalline structure is complex involving different mechanisms of nucleation, diffusion, and growth.

The present study aimed to evaluate the quality of fresh sushi in Egypt. Fifty samples of sushi (Salmo salar) were collected from restaurants in Alexandria, Egypt. Paraffin, semi-thin and ultra-thin sections were used for parasitological analysis by light and transmission electron microscopy. Bacteria were isolated by the dilution plate and direct plate methods and identified by a Vitek system. Twenty (40%) of the total examined samples showed microsporidia and helminth metacercariae infections. Histochemical stains showed distinct pinkish-red pyriform microspores embedded in muscular tissue stained with Gram, periodic acid-Schiff (PAS), and Ziehl–Neelsen (ZN) stains. Semi-thin sections showed double membrane xenoma-inducing granulomas containing spores at different developmental stages. Empty sporophorous vesicles and free spores were observed in the electron microscopic images. A bacteriological assay showed forty samples (80%) contaminated with human pathogenic bacteria with the average total bacterial counts ranging from 32 to 526 CFU/g. Four species of human pathogenic bacteria were identified in the examined samples, namely Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, and Serratia plymuthica in 40, 38, 11, and 6 samples, respectively. These constitute the first record of fresh sushi product in Egypt and indicate the potential pathogenicity associated with raw seafood products.